Pregnancy-associated glycoprotein and progesterone profiles during pregnancy and postpartum in native goats from the north-east of Brazil

Pregnancy diagnosis is a critical procedure for monitoring goat reproductiv e performance. In the present investigation, pregnancy-associated glycoprot ein (PAC) profiles during pregnancy and first month postpartum, as well as progesterone (P-4) concentrations throughout pregnancy, were determined in native goats from the north-east of Brazil. A total of 30 goats (Moxoto, n = 19 and Caninde, n = 11) were used. Peripheral blood was collected on days 0 (Day 0 = AI), 11, 16, 18, 20, 24 and 30 after Al. Samples were subsequen tly collected every 2 weeks until day 145, and weekly during the first mont h postpartum. The levels of FAG and P-4 were determined by radioimmunoassay (RIA). The profiles of FAG were not different between the breeds throughou t pregnancy. However, a significant effect of the week of pregnancy (p < 0. 01) and the number of fetuses (p < 0.05) in FAG concentrations were found. Lower concentrations of FAG were observed during weeks 1 and 3, compared to the rest of the gestation. Thereafter, there was a significant (p < 0.05) increase in FAG concentrations from week 5 to 7 and a significant decrease (p < 0.05) in week 9. The FAG concentrations remained relatively constant u ntil week 17, and finally decreased slowly until parturition. After parturi tion, FAG concentrations decreased rapidly, and continued to decrease until week 4. During pregnancy, mean P-4 concentrations had weekly variations am ong the animals (p < 0.01) and the period of pregnancy (p < 0.01), but P-4 was not affected by the breed or number of fetuses. These results indicate that FAG and P-4 concentrations were similar for Caninde and Moxoto goats a nd that, for both the breeds, the stage of pregnancy and the number of fetu ses could influence FAG production. (C) 1999 Published by Elsevier Science B.V. All rights reserved.